Overhead lifting devices, such as patient lifts used in the health care industry, may generally comprise a lift unit with an actuator, such as an electric motor or similar actuator, coupled to a mechanical lifting arm or cable lift system, such as a lifting strap. The actuator facilitates actuation of the mechanical lifting arm or cable lift system thereby raising and/or lowering a load attached to the lifting arm or cable lift system. The lift unit may be coupled to a rail system with a carriage which facilitates positioning the lift unit with respect to the rail. Positioning the unit along the rail system may be accomplished manually or, in the alternative, with a motor mechanically coupled to the carriage and operable to traverse the carriage and lift unit over the span of the rail system. The actuator and motor may be powered by a battery system positioned in the lift unit. In order to charge the battery system of the lift unit, the lift unit must be periodically coupled to a charging station requiring the lift unit to be moved to specific locations along the rail. Accordingly, during charging, the lift unit may not be used for lifting and transport.
Accordingly, a need exists for alternative mechanisms for continuously powering and/or charging a lift unit as the lift unit is traversed across a rail.